Ktm 600 Lc-4

KTM 600 LC-4

RIDING IMPRESSION

It’s light, it’s powerful, and best of all, it’s finally done

WHEN DEVELOPING ITS NEW 600CC FOUR-STROKE Single, KTM wasn’t in a rush—not unless you consider five years of careful development and meticulous fabrication a rush. But unlike most larger motorcycle factories, the Austrian KTM firm doesn’t have a staff of designers working around the clock on new projects. In fact, KTM has exactly one designer qualified to work on the development of a Thumper—and he already had a busy schedule before launching into the 600cc project. Nonetheless, the long-awaited KTM Thumper did eventually get designed and built, and it soon will be making its way to this country.

Dubbed the LC-4, the new KTM has a 553cc sohc engine with a 95mm bore and 78mm stroke, and it is claimed to produce 50 horsepower. A 38mm Dell’Orto carburetor feeds the big lunger, and an SEM ignition with 140-watt lighting coils fires the fuel and powers the lights.

Like Husqvarna’s 510 four-stroke, the LC-4 has, at a claimed 72 pounds, a very light engine. The KTM also uses an oiling system similar to the Husky’s, with lubrication in the lower part of the engine accomplished solely by the splash method; but unlike the Husky, the KTM has an oil pump that feeds the top-end, as well as a cooling system that employs a thermostat and an electric water-pump.

During a day-long ride on a pre-production LC-4, we found that the power output was plentiful yet very linear and controllable. When running, the engine always carburated cleanly; but because the carb jetting for U.S. models had not yet been finalized, cold starts were unpredictable, requiring anywhere between one and 20 kicks.

And although the shifting of the five-speed gearbox felt a little notchy, engagement was very positive.

On the other hand, the White Power suspension components on the machine we rode had been finalized, and we found they had near-perfect spring and damping rates. The suspension always provided a smooth ride over small bumps, and excellent control and comfort at high speeds.

Matter of fact, during on our ride aboard the pre-production LC-4, we found little to complain about. The slim plastic gas tank is mounted low on the rugged frame, and the seat is nicely shaped and made of comfortable, medium-density foam. The bike will come with an enduro headlight and rear fender/taillight, and with a motocross front numberplate and rear fender. That way, one model should fit every need.

Without gas, the bike we rode weighed 263 pounds (with enduro headlight and rear fender); but the U.S. production model will have an aluminum silencer/spark arrester in place of the steel, street-legal European silencer on the pre-production bike. And several steel brackets that are not needed on the American model will be deleted. So the actual production bike will probably come close to KTM’s advertised 253-pound dry-weight claim.

That’s light for a production 600 four-stroke Single. And that lightness, combined with the bike’s superb overall performance and high-grade components, should make the LC-4 a worthwhile investment.

That’s saying a lot, considering the LC-4’s projected retail cost of $4395. But quality-and five years of development—doesn’t come cheaply. 0